Thermoelectric water cooler



United States Patent f 3,368,359 THERMOELECTRIC VATER COOLER William A. English, Export, Robert S. Lackey, Pittsburgh,

and Jack D. Meess, Export, Pa., assignors to Westinghouse Electric Corporation, Pittsburgh, Pa., a corporation of Pennsylvania Filed July 19, 1966, Ser. No. 566,268 4 Claims. (Cl. 62-3) ABSTRACT OF THE DISCLOSURE Heat dissipator apparatus for a thermoelectric type water cooler having a one-piece integral block provided with a series of upright passages and at least one interconnecting passage containing a liquid vapor phase fluid, and a series of tubes connected to the top ends of the upright passages and extending away from the block so that heat is dissipated by boiling the liquid in the block and condensing the liquid in the tubes for dissipating the heat.

This invention relates to a heat dissipator arrangement for a thermoelectric water cooler such as is disclosed in TerBush patent application U.S. Ser. No. 539,526, filed Apr. 1, 1966, now Patent No. 3,327,485.

The TerBush patent application discloses a thermoelectric water cooler arranged to facilitate the rapid replacement of the cooling package. The cooling package is a substantially unitary assembly generally comprising a water cooling tank, a thermoelectric module, and heat dissipated means. The thermoelectric module is sandwiched between the tank and the heat dissipator and op erates to extract heat from the cooling tank and transfers the heat to the atmosphere through the heat dissipator.

Our invention is specifically concerned with the struc ture of the heat dissipator. It essentially comprises a closed system boiler and condenser containing a liquid vapor phase refrigerant. According to the preferred embodiment of our invention, the boiler takes the form of a block having good thermal conductivity disposed with one face in heat exchange relation with the structure passing heat from the thermoelectric module. The block is an integral member provided with a series of upright passages closed at the bottom and open at the top face of the block, and having at least one generally horizontal passage interconnecting the upright passages. The boiler may be made from a steel block in which the upright passages are drilled down through the top edge face of the block to depths short of the bottom face of the block. One or more horizontal passages may be drilled from one side edge face to interconnect the upright passages. The top end of the upright passages may be counterbored to receive the bottom ends of individual vapor tubes which are received in the counterbores and sealed to the block by welding or brazing. Each tube extends upwardly away from the top edge of the block and serves as a closed vapor loop. Wires are preferably wrapped transversely of the tubes to increase the heat transfer capability of the tubes. The block is evacuated and then charged with a refrigerant such as R-12, the amount of refrigerant being approximately that which fills the boiler upright passages with liquid refrigerant, and the tubes with vaporous refrigerant. The boiler charging inlet is then closed so that the system as a whole is sealed.

The invention will be described in connection with the accompanying drawing illustrating a currently preferred embodiment, and wherein:

FIGURE 1 is a partly broken side view of a thermoelectric water cooler provided with a heat dissipator arrangement according to the invention;

FIG. 2 is an isometric view of the heat dissipator;

Patented Feb. 13, 1968 FIG. 3 is a partly broken rear face view of the boiler and lower ends of the vapor tubes; and

FIG. 4 is an edge view of the boiler of FIG. 3.

The principal parts of the thermoelectric water cooler of FIG. 1 include the cabinet and frame structure 10 which carries a cooling package generally designated 12 fastened to the upper portion of the cabinet. A water bottle 14 mounted in inverted position on the top of the cabinet supplies water to a cooling tank 16 encompassed by insulation and a casing 18. The cold producing system of the cooling package includes a cold shoe 20 having one face countoured to abut closely a part of the circular exterior face of the cooling tank 16, a thermoelectric module 22 sandwiched between the cold shoe and a heat sink plate 24, the boiler 26 which is clamped with its one face tightly against the heat sink plate, and a number of vapor tubes 28 extending upwardly and away from the cabinet out of the top edge of the boiler.

The exterior appearance of the boiler 26 and connected vapor tubes 28 is best shown in FIG. 2. In the arrangement of the example, six vapor tubes 28 are provided and alternate ones of the tubes are bent out of the upright plane of the other three tubes so that increased spacing between the tubes is provided in the area where they dissipate the heat to the surrounding air. To enhance heat transfer from the tubes to the air, the tubes lying in each vertical plane are wrapped with wire 30 so that two separate wire and tube condensers are formed.

The structure of the boiler and its manufacture will now be explained in connection with FIGS. 3 and 4. A series of spaced, upright passages 32 are drilled down into the block through the upper edge face 34 to depths short of the bottom face 36 of the block. The upper ends of the passages 32 are provided with counterbores 38 which receive the bottom open ends of the vapor tubes 28. Preferably, two horizontal interconnecting passages 40 and 42 are drilled through a side edge face 44 to interconnect both the bottom portions, and the top portions of the upright passages. After drilling the horizontal passages 40 and 42, which stop short of the opposite side of edge face 44, the horizontal passages are sealed with plugs 46 and 48. An additional passage 50 may be drilled up into the block to provide an evacuating and charging connection.

The currently preferred method of making the boiler as an integral member is to use a steel block and drill the holes therein. It has been found that a block about one inch thick and provided with vertical passages 32 of about /8 inch diameter, and an upper horizontal passage of the same diameter and a lower passage of about inch diameter, provides quite satisfactory results. The bottom interconnecting pasageway tends to maintain equal levels of liquid refrigerant in the various upright passageways in the boiler. While it is not mandatory to have the top horizontal passage 40, it is considered to be good practice to provide the interconnection near the top of the passages to promote uniformity of heat transfer for the width of the boiler block and to reduce the chance of hot spots.

After the block has been drilled and plugged, the individual vapor tubes 28 are secured in the counterbores by brazing or welding depending upon the material of which the tubes and block are made. While the tubes can be in the form of hairpin loops, with the illustrated non-return tube shape, each tube 28 is closed at the top so that the boiler and tubes together provide a closed system. The block is evacuated through charging passage 50 and the system is then charged with a refrigerant such as R-IZ with an amount sutficient to approximately fill the upright passages 32 with liquid refrigerant, and with a relatively low density vapor existing in the tubes above the level of the liquid.

In operation of the device, the heat from the hot side of the thermoelectric module passes through the heat sink plate and into the block where it vaporizes liquid refrigerant. The vapor passes up into the tubes 28 and is condensed as it releases its heat to ambient air about the tubes and wires. The condensed refrigerant flows down the sides of the tubes 28 to repeat the cycle of vaporization and condensation. In typical operation the refrigerant temperature may be, say, 120-125 F. with the corresponding gauge pressure of about 157-168 p.s.i. for R-12.

The provision of a solid boiler which is drilled gives a system with relatively low thermal drop because of the minimal number of interfaces and large internal area. The block construction is also advantageous in avoiding strength problems for the pressures involved.

We claim as our invention:

1. In a water cooler of the thermoelectric module type, a heat dissipator comprising:

a block of a material having good thermal conductivity disposed with one face in heat exchange relation with structure passing heat from said module, said block being a one-piece integral member having a series of upright passages closed at the bottom and open at the top face of the block, and having at least one generally horizontal passage interconnecting said upright passages;

a tube having a bottom open end connected in sealed relation to the open top end of each upright passage, each said tube extending away from said block; and

a liquid vapor phase fluid in said block and tubes.

2. A device according to claim 1 wherein:

said block includes said one generally horizontal passage at the lower end of said upright passages, and another generally horizontal passage adjacent the top end of said upright passages.

3. A device according to claim 1 wherein:

said vertical passages are substantially aligned with each other and uniformly spaced across the Width of said block; and

alternate ones of said vapor tubes have substantial portions thereof displaced out of the planes of the remaining vapor tubes.

4. In a device according to claim 1:

said block comprises a steel member, and said upright passages comprise bores drilled into said steel block.

References Cited UNITED STATES PATENTS WILLIAM J. WYE, Primary Examiner. 

